Method of treating piston and cylinder surfaces



G. W DQNNELLY v METHOD OF TREATING PISTON AND CYLINDER SURFACES Filed Sept. 50. 1922 anneal o1,

firm mu I Fatented 9st. 30, 1923.

GEORGE W. DONNELLY, OF ROUZERVILLE, PENNSYLVANIA.

METHOD OF TREATING PISTON AND CYLINDER SURFACES.

Application filed September 30, 1922. Serial No. 591,586.

To all whom it may concern:

Be it known that I, GEORGE W. DoNNnL- LY, a citizen of the United States, residing at Rouzerville, in the county of Franklin and State of Pennsylvania, have invented certain new and useful Improvements in Methods of Treating Piston and Cylinder Surfaces, of which the following is a specification.

The present invention relates to methods of dressing or putting a final finish upon the coacting surfaces of engine pistons and cylinders so as to produce faces that will effectively retain a film of oil, thereby sealing the joint and insuring the same against leakage with consequent loss of power.

' In the accompanying drawings Figure 1 is a perspective View indicating a simple means for carrying out the method in treating the 'piston surface,

Figure 2 is a view illustrating the means that may be employed for operating on the 7 cylinder in which said piston is placed,

Figure 3 is a detail sectional view on the line 33 of Figure 2.

I11 carrying out the invention the surface A of a piston designated B is lightly honed. This may be accomplished by any suitable means, and in the present disclosure :1 hone C is shown as being manually operated. This manipulation in'eferably is in a generally gyratory course as indcated by the dotted line D. The hone may also be slightly concaved, as illustrated at E. This hone is of a fine texture, such as is used in the honing of razors or other sharp-edged instruments.

It is applied by a light pressure and the entire surface gone over. The same can be accomplished with great expedition n1anually as indicated in Figure 1 of the drawing.

The coacting surface of the cylinder, which is indicated at F in F igurcs 2 and 3, is similarly treated, the edges G of the hone being preferably convexed so as to provide a rounded surface that will act upon the surface of the cylinder.

Actual experience has demonstrated that this -ressing or treatment provides coacting surfaces of a character that will effectively hold a film of oil between them and thus seal the joint. In the case of internal combustion engines, it results in a high degree of compression, in that it elin'iinates leakage. Indeed it has been found that this is true, even with worn pistons, and that it is unnecessary to have tight fitting rings therein.

Having thus fully described my invention, what I claim as new, and desire to se cure by Letters Patent, is;-

The method of finishing the (reacting sur faces of the-cylinders and pistons of en gines, which consists in completely honing said coacting surfaces with a light pressure and a generally gyratory Il'lOiTlOE'L In testimony whereof I affix my signature in the presence of two witnesses.

GEORGE W. DONNELLY.

Witnesses:

ROY E. FRIEDLY, JOHN A. POTTER. 

